Container end closure



Sept. 8, 1959 H. c. HOPKINS CONTAINER END CLOSURE 2 Sheets-Sheet 1 FiledMay 9, 1956 INVENTOR HARVEY C. HOPKINS Sept. 8, 1959 H. c. HOPKINS2,903,173

CONTAINER END CLOSURE Filed May 9, 1956 2 Sheets-Sheet z INVENTOR HARVEYC. HOPKINS United States Patent CONTAINER EN D CLOSURE Harvey C.Hopkins, Chappaqua, N.Y., assignor to King Container Corporation, NewYork, N.Y., a corporation of New lersey Application May 9, 1956, SerialNo. 583,860

21 Claims. (Cl. 229---5.5)

The invention relates to a novel container and closure therefor, andparticularly to a new system of closing and reopening a rectangular endof a container. The closure includes an arrangement for using easilytearable sheet material to seal part of the closure on the container,and for using a relatively stiff portion of the closure to cut edgewisethrough said material during the opening of the closure. While theclosure is primarily intended for containers of single use products, ithas the advantage of being convenient to reclose when it is desired toremove only part of the contents of the container.

The closure is especiaily adapted for use with containers of rectangularcross-section, which is the shape ideal for storing and shipping themaximum quantity of product in a given space. The closure and containermay be fabricated separately, and then assembled, or the containerside-seam may be sealed on the same equipment which attaches theclosure. The latter procedure is particularly convenient when thecontainer bodies are shipped flat to be assembled at a packing plant,since the closure members are preferably shipped separately in rolls andare cut to shape and combined as they are assembled to the bodies at thepacking plant.

For a better understanding of the invention, reference is now made tothe present preferred embodiment of the invention shown, for purposes ofillustration only, in the accompanying drawings. In the drawings:

Figure 1 is a perspective View of a container closed at the upper endwith a closure embodying the invention;

Figures 2 and 3 are vertical sections through the planes indicated at 22and 3-3 in Figure l, with the lower portion of the container brokenaway, and with the open position of the closure indicated in dottedlines in Figure 2.

Figure 4 is a perspective view showing the foil and paperboardcomponents of the closure of the invention in their original flat form,and spaced apart for the purposes of illustration;

Figure 5 is an enlarged plan view of the closure of the invention in itsoriginal fiat form, with the paperboard component above the foilcomponent;

Figure 6 is a view corresponding to Figure l, but in reduced scale andshowing the closure on the container before the opposite end flaps andfoil tongues are folded into final position; and

Figure 7 is a view corresponding to Figure 6, after the foil tongueshave been folded into final position, but with the end flaps still up.

The illustrated embodiment of the invention comprises an end closure 10,and a container 12 of rectangular cross-section on which the closure ismounted (Figures l-3). The closure 10 is a laminate consisting of apaperboard component 14 secured by heat-bonding adhesive 16 to a foilcomponent 18. Other relatively stiff material may be substituted forpaperboard in component 14, and other material which is effective forsealing and is relatively easy to tear, such as plastic film, cellophaneor treated paper, or various sheet laminates, may be substituted forfoil in component 18.

As shown in Figures 4 and 5, the paperboard component 14 of the closure10 has a rectangular central area 22 bounded by four score lines 2427which respectively mark the line of division between the central area 22and four rectangular flaps 2932. The opposite side flaps 30 and 32 areof equal size, are relatively narrow, and have no additional scorelines. The end flap 31 is about twice as wide, measured from the scoreline 26, as the side flaps 30 or 32 measured from the score lines 25 or27, and has an additional score line 34 extending across its lengthparallel to the score line 26, and spaced the same distance from thescore line 26 as the outer edges of the side flaps 30 or 32 are spacedfrom the respective score lines 25 or 27. The other end flap 29 has ascore line 36 extending across its length parallel to the score line 2and spaced the same distance therefrom as the spacing between scorelines 26 and 34. However, the end flap 29 is substantially longer,measured from the score line 36, than the end flap 31 measured from thecorresponding score line 34. All of the score lines are preferablyscored on both sides of the paperboard to facilitate bending.

In order to facilitate opening the closure, a coating of wax 33 isapplied to the whole area of the non-foil covered side of flaps 30 and32, to the area of the non-foil covered side of flap 29 between scorelines 24 and 36, and to the non-foil covered side of flap 31 betweenscore lines 26 and 34. The wax 33 prevents these areas from sticking tothe opposite surfaces of the container body walls during the process ofheat-sealing the closure on the container body, regardless of thepresence of an underlying coating of heat bonding material on the saidflap-s, or on the container body walls. On the other hand, in order toanchor the closure on the container body, a heat-bonding adhesive 35 isapplied to an area of the nonfoil covered side of flap 29 equal to thearea between score lines 24 and 36, but on the other side of score line36, and to the non-foil covered side of flap 31 between the score line34 and the end edge of flap 31. A further consideration is to protectthe inner surfaces of the paperboard member 14 from penetration by theproduct packed in the container, and one procedure in accordance withthe invention is to apply a thermoplastic protective coating to the rollof paperboard from which the paperboard members 14 are cut, on the sidewhich is not covered with foil (preferably in a central stripecorresponding to the area of the end flaps 29 and 31, and the centralarea 22, but omitting the area of the side flaps 30 and 32). Such acoating will not only act as a protective coating where needed, but alsowill serve as the above-mentioned adhesive 35 on the desired areas ofend flaps 29 and 31. If such coating is used, subsequent application ofwax 33 as described above is necessary. If such coating is not used,adhesive 35 is preferably spot printed in the areas stated above, andwax 33 can then be omitted, unless it is required by reason of thepresence of a like coating on the container body walls.

The foil component 18 covers the entire area of one side of thepaperboard component 14, and is co-extensive with the outer edges of theend flaps 29 and 31. In addition, the foil component 18 has webs 37extending across the triangular space where each end of each of the sideflaps 30 and 32 makes a corner with the adjacent end of the end flaps 29and 31 between the score lines 24 and 36, in the case of flap 29, andbetween the score lines 26 and 34, in the case of flap 31. Thesetriangular webs 37 are each folded along lines extending radially fromthe said adjacent corners, and the adhesive-coated areas thereof whichare folded together are sealed during the final mounting of the closureon the container, in

order to insure a protective seal at the inside corner where each of thetriangular webs 37 is located. The foil component 18 also has tworectangular extensions 38 and 40 projecting beyond the outer edges ofthe side flaps 30 and 32, these extensions being longer in bothdirections than the side flaps 30 and 32, so that they respectively havetongues 42 and 44 paralleling and extending as far as the end flap 29,and tongues 43 and 45 paralleling and extending as far as the end flap31. The foil component 18 thus has a rectangular area of the same lengthas the paperboard component 14- between the outer edges of its end flaps29 and 31, but of greater width than the paperboard component 14 betweenthe outer edges of its side flaps 3i) and 32, and has four notches 39extending in pairs from opposite ends of the rectangular area of thefoil component 18 to define the outer edges of the webs 37 and end flapportions of the foil, and the inner edges of the foil tongues 4245.

The foil component 18 is coated with the adhesive 16 entirely over oneside, and is subsequently bonded to the prescored paperboard component14. That bonding op eration does not affect the adhesive 16 on the foilwebs 37, the foil extensions 38 and 49, and the foil tongues 4245, andconsequently that adhesive is available for subsequent use in sealingthe closure on the container body. Such construction is adapted forefiicient production, such as by trimming a strip of paperboard to theshape of a series of the components 14 integrally joined with the outeredge of the flap 23 of one unit connected to the outer edge of the flap31 of the next unit; scoring each component 14 with the scorelines 2427,34 and 36, on both sides of the paperboard strip; passing the stripthrough heated pressure rolls against a wider strip of foil coated withthe adhesive 16 on the side of the foil against the paperboard, so thatthe two strips are bonded together; applying adhesive 35 and wax 33 tothe non-foil covered side of the paperboard, where necessary, aspreviously described; and simultaneously cutting apart the laminatedunits and cutting the notches 39 in the foil component 18.

When the closure is sealed on one end of the body 46 of container 12,the body 46 is preferably held on a conventional mandrel which extendsthrough the open bottom of the body 46, against the body side walls485l, to a level spaced from the top of the body 45 by a distancesubstantially equal to the spacing between score lines 24 and 36, and 26and 34, respectively, which spacing equals the width of the side flaps3t and 32 as measured from the score lines 25 and 27, respectively. Theclosure 14, with the foil component 18 above the paperboard component14, is bent along the score lines 24-27 to raise the flaps 29-32, and isheld by a conventional chuck while being inserted in the upper end ofthe body 46 to a depth substantially equal to the above mentionedspacing between score lines 24 and 36, and 26 and 34, respectively. Thefoil extensions 38 and 40 are bent over the top edges of body sides 48and 50, and are brought down against the latter sides, The tongues 42and 44 are folded around the outside of the upper end of body wall 49,and the tongues 43 and 45 are folded around the outside of the upper endof body wall 51 (Figures 6 and 7) these tongues strengthen the corners,but may be omitted. The end flaps 29 and 31 are then bent alongscorelines 36 and 34 and folded down over those sides, and over thetongues 42 and 44, and 43 and 45. The webs 37 are folded outwardly ofthe four corners formed when the flaps 29-62 are initially bent up onscore lines 2427, and are subsequently crimped between said corners andthe adjacent inside corners formed by the upper ends of the body walls48-51. One or more heating irons, successively or simultaneously, areapplied against the outside of the downturned foil extensions 38 and 40,against the downturned portion of flap 31, and against an equal area atthe top of the downturned portion offlap 29, until the adhesive 16 bondsthe foil extensions 38 and 40 to the upper ends of the body sides 48 and50, bonds the foil tongues 42 and 44 to the upper end of body wall 49,bonds the foil tongues 43 and 45 to the upper end of body wall 51, andbonds the crimped webs 37 between the obtuse corners formed by theupturned closure flaps 2932 and the acute corners formed by the bodywalls 48--51; and until adhesive 35 bonds the upper part of thedownturned portion of end flap 29 to the outside of body wall 49 and tothe foil tongues 42 and 44, and bonds the end flap 31 to the outside ofthe upper end of container wall 51, and to the foil tongues 43 and 45.Such bonding thoroughly seals the closure 15) on the end of thecontainer body 46. No heat or pressure is applied to the lowermost endportion of flap 29, in order to leave it unbonded and available as aconvenient tab 54 for opening the closure. After the closure 10 has beenapplied, the container body 46 may be filled, and then closed at itsopposite end by conventional means.

The closure 10 is opened by grasping the unbonded tab 54 formed by thelower end of the flap 29, and pulling it up to tear away the part of theflap 29 bonded by adhesive 35 to the outside of the container body sidewall 49. Continued pulling of the flap 29 breaks the seal at webs 37adjacent flap 29, causes the side flaps 30 and 32 to swing upwardly andwith their upper edges cut through the foil which passes over and sealsthe juncture of said flaps with the container walls 48 and 50, andfinally pivots the closure on the score line 34 through any desiredangle (up to about 270), whereby the end of the container may be openedas much as may be desired. However, the closure is preferably swung upless than which keeps part of each of the side flaps 39 and 32 againstthe inside of the adjacent body walls 50 and 48 (Figure 2) and thusfacilitates swinging the closure back to its original closed position.The return movement is further facilitated by the fact that the portionof end flap 31 beyond its score line 34 remains bonded to the outside ofthe upper end of body wall 51, so that the closure is accurately guidedback to closed position by swinging about the score line 34 as a fixedpivot axis relative to the container body. The side flaps 3d and 32 arenot bonded to the container body, but act as transverse stitfeners ofthe closure, and, as mentioned above, are carried upwardly like knives,when the opening movement of the closure begins, so that their upperedges cut through the adjacent portions of the foil extensions 38 and40, thus freeing the closure to continue its opening movement. When theopened closure is returned to closed position, the original hermeticseal is broken, except along the flap 31, but the contact of the sideflaps 30 and 32 with the inside of the body walls 50 and 48 and of theflap 29 with the inside area and top edge of the body wall 49, togetherwith the unbroken seal along the flap 31, provide an adequate seal atthe top of the container for purposes of temporary storage.

The closure 10 can also be applied in reverse position, with thepaperboard component 14 on the outside. In that case the foil component18 is coated with adhesive where it lies against the paperboardcomponent 14, and the other side of the foil component 18 is coated withadhesive wherever the foil extends beyond the paperboard, and is coatedwith adhesive and wax, respectively, on the areas of the foilcorresponding to the areas of the paperboard component 14 which havebeen described above as covered with adhesive 35 and wax 33 (see Figure5).

As a further improvement, the upper end of the container body 46 can benecked in so that in packing the containers the upper end will nestinside the walls of the lower end, the latter being fitted with a bottomclosure which is channeled to receive the walls formed by the bent-overflaps of the closure 10, but has a downwardly dished central areaadapted to fit against the area 22 of the closure 10. That arrangementprotects the closure '10 from transit damage, and saves some of thespace which would otherwise be lost as a result of having recessed ends.1

While I have illustrated and described a present prefer-red embodimentof the invention, it will be understood that it may be otherwisevariously embodied and practiced within the scope of the followingclaims. I

l. A paperboard container comprising a body having four sides forming arectangular opening at one end of the body and a rectangular closure forthe opening, said closure formed of a sheet of paperboard and a sheet ofsealing material secured together, said closure hinged at one side toone of the container walls, said sheet of sealing material bonded to theexposed outer' surface of said paperboard sheet and extending beyond thepaperboard sheet and secured to the outside of the container walls andmeans integrally connected to said closure adapted to sever thesealingmaterial whereby access to the interior of the container isgained, said last mentioned means inclulding an upwardly extending flapon each side of the closure adjacent the hinged side, a surface of eachflap resting flush against a surface of the adjacent walls of thecontainer body. a

2. A paperboard container comprising a body having four sides forming a.rectangular opening at one end of the body, and a rectangular closurefor the opening, said closure having one side hinged to one of the sidewalls, an upwardly extending flap carried by the closure on each of thesides adjacent to the hinged side, an easily tearable sheet materialbonded to the outer surface of said closure adapted to seal the closurein the rectangular opening, said sheet material extending over the upperedges of said upwardly extending flaps and secured to the outside of thetwo adjacent container walls, whereby the upper edges of said flaps s erve as knife-edges to sever the sealing material when the closure isswung upwardly about its hinge. i

3. A paperboard container comprising a body having four sides forming arectangular opening at one end of the body, and a rectangular closurefor the opening, said closure having one side hinged to one of the sidewalls, flaps on the rem-ainingthree sides of the closure, said threeflaps bent upwardly, whereby they press lightly upon the adjacentcontainer walls, an easily tearable sheet material bonded to the outersurface of said closure adapted to seal the closure in the rectangularopening, said sheet material extending over the upper edges of the twoflaps adjacent the hinged side of the closure, the upper edges of saidtwo flaps severing the sealing material when the closure is swungupwardly about its hinge in opening the container, and said three flapsproviding a reseal when the closure is swung downwardly to close thecontainer.

4. A container comprising a body having four side walls forming arectangular opening at one end of the body, and a closure sealing saidopening and comprising a first component of relatively stiif sheetmaterial, said first component having a central area extending acrossthe said opening at a level spaced inwardly from the ends of the wallsforming said opening, and having a pair of flaps extending integrallyfrom two opposite sides of the central area, and overlapping both sidesof the ends of the adjacent pair of opposite walls forming said opening,both of said flaps being bonded to the said adjacent walls, but one ofsaid flaps having an exterior, downwardly extending extremity which isnot bonded to the adjacent wall surface; and said closure comprising asecond component of easily tearable sheet material overlying and bondedto the first component, and having extensions beyond the first componentwhich are bonded to the other of said pairs of opposite walls to sealthe said opening, said downwardly inclined first component flapextremity adapted to lift one end of the closure whereby the secondcomponent will be torn, and the container opened.

5. A container according to claim 4, in which the first "6 closurecomponent is of paperboard, and the second closure component is of metalfoil. f

6. A container according to claim 4, in which the flap having saidextremity is not bonded to the interior wall surface overlapped by saidflap, and the other flap is not bonded to the interior wall surfacewhich it overlaps.

7. A container according to claim 4, in which the first component ofsaid closure has a second pair of flaps extending integrally fromopposite sides of said central area at right angles thereto, said flapsextending against the adjacent side walls of the container body up tobut not beyond the edges of said walls forming said opening, and beingunbonded to said side walls; and in which said second component of theclosure extends over said second pair of flaps and down the exteriorsurfaces of the side walls adjacent said flaps, and is bonded to saidexterior surfaces.

8. A container according to claim 7 in which the portions of the secondcomponent extending past the second pair of flaps over the exteriorsurfaces of the adjacent container body walls, each have an extensionwrapped around an adjacent exterior corner of the container and bondedbetween one of the first pair of flaps and the adjacent container bodywall.

9. A container according to claim 7 in which the poltions of the secondcomponent extending past the second pair of flaps over the exteriorsurfaces of the adjacent container body walls, each have an extensionWrapped around an adjacent exterior corner of the con tainer and bondedbetween one of the first pair of flaps and the adjacent container bodywall, and an opposite extension wrapped around the adjacent exteriorcorner of the container and bonded between the other of the first pairof flaps and the adjacent container wall.

10. A container according to claim 7 in which a crimped web of thesecond component extends across each corner formed between adjacent endsof the two pairs of flaps.

11. A container comprising a body having four side walls forming arectangular opening at one end of the body, and a closure sealing saidopening and comprising a first component of relatively stiff sheetmaterial, said first component having a central area extending acrossthe said opening at a level spaced inwardly from the ends of the Wallsforming said opening, and four substantially rectangular flaps extendingintegrally from said central area at right angles thereto against theadjacent interior surfaces of the side walls toward said opening, onepair of said flaps on opposite sides of the central area being ofunequal length, the shorter flap being folded over the end of theadjacent wall and bonded to at least the exterior surface of said wall,and the longer flap being folded over the end of the adjacent wall andbonded to the exterior surface of said wall only adjacent its end,thereby leaving an unbonded outside tab at the end of the longer flap;the other pair of flaps being shorter, extending only to the opening,and being unbonded to the container side walls; and said closurecomprising a second component of flexible and readily tearable sheetmaterial, which overlies and is bonded to the outer portions of thefirst component within the opening, and has extensions, beyond thesecond pair of flaps which are folded over the ends of the side wallsadjacent the second pair of flaps, and are bonded to the exteriorsurfaces of the latter walls.

12. A container comprising a body having four side walls forming arectangular opening at one end of the body, and a closure sealing saidopening and comprising a sheet of relatively stiff material, said sheethaving a central area extending across the said opening at a levelspaced inwardly from the ends of the walls forming said opening, andfour substantially rectangular fiaps extending integrally from saidcentral area at right angles thereto against the adjacent interiorsurfaces of the side walls toward said opening, one pair of said flapson opposite sides of the central area being of unequal length, the

'shorter flap being folded over the end of the adjacent Wall and bondedto at least the exterior surface of said wall, and the longer flap beingfolded over the end of the adjacent wall and bonded to the exteriorsurface of said wall only adjacent its end, thereby leaving an unbondedoutside tab at the end of the longer flap; the other pair of flaps beingshorter, and extending toward but not beyond said opening.

13. A closure for the rectangular end of a container, comprising a firstcomponent of relatively stiff sheet material, having a rectangularcentral area and four integral flaps extending one from each border ofthe central area,

one pair of flaps on opposite sides of the central area extendingequally from the adjacent border thereof, the third flap extending abouttwice as far from the central area, and the fourth flap extending stillfurther from the central area; and a second component of flexible andreadily tearable sheet material, the second component being bonded oversubstantially the whole external area of the first component, andextending beyond said first component to form a web between adjacentside edges of the flaps at each corner of the said central area, andalso to form an extension beyond each of the first-mentioned pair offlaps.

14. A closure according to claim 13 in which the first component ispaperboard, and the second is metal foil.

15. A closure according to claim 13 in which each of the extensions ofthe second component has a pair of oppositely extending tonguesprojecting in the direction of the said third and fourth flaps,respectively.

16. A closure according to claim 13 in which adhesive covers the entiresurface of one side of the second component, including its extensions,and part of said adhesive bonds the two components together.

17. A closure according to claim 13 in which score lines are scored inthe first component where each flap joins the central area, and acrossthe third and fourth flaps parallel to the score line at the base of theflap and spaced from the latter score line by a distance equal to thespace between the score line at the base of each of the first pair offlaps and the parallel outer edge thereof.

18. A closure according to claim 17 in which adhesive covers a certainarea of the side of the third flap not bonded to the second component,the said certain area lying between the outer edge of the third flapparallel to the score lines across said flap, and the score line nearests said edge; and in which adhesive covers a certain area of the side ofthe fourth flap which is not bondedto the second component, the lattercertain area being between the outer edge of the fourth flap and thenearest score line across that flap, and being adjacent said score lineand spaced away from said edge.

19. A closure according to claim 17 in which a nonadherent coatingcovers certain areas on the side of the first component not bonded tothe second component,

said areas extending across substantially the whole of the first andsecond flaps, and between the two score lines across the third flap andthe two score lines across the 'fourth flap.

20. A container comprising a body having a dispensing opening and aclosure for said opening, said closure having at least a portion thereofhinged to the container body, at least a pair of flaps terminating inedges carried by the closure one on each side of the hinged portion,frangible material bonded to the outer surface of at least theperipheral area of said closure adjacent said flaps, a portion of saidmaterial extending beyond said flaps is secured to the surface of thecontainer adjacent said flaps and adapted to seal the closure within thedispensing opening, said flap edges severing the frangible material whenthe closure is swung upwardly about its hinge.

v 21. A container as defined in claim 20, including means integral withsaid closure extending beyond the borders of the dispensing opening andsealed to the outer surface of the container when the closure is in aclosed position, said means adapted to swing said closure upwardly aboutsaid hinge when a lifting force is applied to said means.

References Cited in the file of this patent UNITED STATES PATENTS1,152,355 Sutton Aug. 31, 1915 1,707,946 Roth Apr. 2, 1929 2,152,400 DaRold Mar. 28, 1939 2,290,749 Hildebrandt July 21, 1942 2,398,405 BrooksApr. 16, 1946 2,465,842 Brooks Mar. 29, 1949 2,665,616 Jungmayr Jan. 12,1954 2,757,851 Moore Aug. 7, 1956 FOREIGN PATENTS 4,690 Great Britain1910 479,059 Great Britain Jan. 31, 1938 1,078,705 France May 12, 1954

